Drugov, M. V.; Barantsevich, E. N.; Smirnov P. A. Journal of Organic Chemistry USSR (English Translation), 1984 , vol. 20, # 6 p. 1052 - 1056 Zhurnal Organicheskoi Khimii, 1984 , vol. 20, # 6 p. 1157 - 1162